Lost Tale of a Lost Dwarven Tribe and Thranduil?

[Kuruharan]

I have to admit that the wording there is rather curious.

Maybe he had had some pacts with those enigmatic dwarves from the Grey Mountains (not Durin's folk, mind you!).

The only dwarves we know about in the Grey Mountains were Durin's Folk. I don't think there is any traction there.

Hmmm...this one requires more pondering.